Thyroid imaging

The thyroidal mechanism used for concentrating 1 may also concentrate other monovalent anions, including pertechnetate, perchlorate, and thiocyanate, within the follicular lumen. However, none of these anions become incorporated into Tg, although they may act as a competitive inhibitor of 1 transport. The ability of the thyroid gland to concentrate radioactive pertechnetate makes it a useful agent for thyroid imaging, since it is concentrated by the thyroid cells without further metabolism. The perchlorate and thiocyanate discharge tests make use of the ability of these anions to inhibit 1 transport to test for defects in the incorporation of 1 into Tg. 

The clinical, biochemical, and thyroid imaging characteristics of thyrotoxicosis resulting from interferon alfa treatment have been retrospectively analysed from data on 10 of 321 patients with chronic hepatitis (75 with chronic hepatitis B and 246 with chronic hepatitis C) who developed biochemical thyrotoxicosis (505). Seven patients had symptomatic disorders, but none had ocular symptoms or a palpable goiter. Six had features of Graves disease that required interferon alfa withdrawal in four and prolonged treatment with antithyroid drugs in all six. Three presented with transient thyrotoxicosis that... 

Subtraction Previously injected activity in thyroid gland is subtracted from the total neck image ( Tc-sestamibi -I- 1- or " Tc-thyroid image) (Wei et al. 1992). 

Tc pharmaceuticals mark the begiiming of diagnostic nuclear medicine and have contributed to patient care worldwide. Since the short-lived radionuclide was introduced for thyroid imaging in 1964, it has attracted much attention and stimulated clinical research. Little was known about element 43, except that it was an artificial radionuclide obtained by the radioactive decay of molybdenum-99. No wonder specialists from all fields joined medical institutions in the United States to participate in the exploration of its chemistry. 

LABELLED IODINE-123 COMPOUND Iodine-123 is an important isotope produced by MDS Nordion s cyclotron operations in Vancouver. It is used in brain, heart, and thyroid imaging. 

In XRF thyroid imaging systems using Am, two basic geometric types are offered on the most recent models ... 

Table 5 Width of the radiation source beam expressed as the full width at half maximum (FWHM) of the response to an iodine line in the focal plane for some XRF thyroid imaging systems.

Johnson PM, Esser PD, Lister DB. 1979. Fluorescent thyroid imaging clinical evaluation of an alternative instrument. Radiology. 130 219-222. 

Hoffer PB, Bernstein J and Gottschalk A. 1971. Fluorescent techniques in thyroid imaging. Seminars in Nuclear Medicine, I, 379. 

The "in vivo" measurement of total intrathyroidal stable iodine by X-ray fluorescence (XRF) was originally considered as a means of collecting additional information making use of an XRF device (fluorescent scanner) designed primarily for thyroid imaging (1-6). 

An analysis of the various XRF devices with respect to their cost and performances in studies on the thyroid (imaging, iodine quantitation and dynamic study) can be found in ref. (10). The present report focuses on the basic physical and technical aspects of intrathyroidal iodine quantitation by means of XRF, particular at-... 

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